Tomato Leaf Curl Virus Vector (Bemisia biotype)

📖 Description

Tomato Leaf Curl Virus Vector (Bemisia tabaci biotype B), also called Silverleaf Whitefly or B Biotype Whitefly, is the most important vector of Tomato Leaf Curl Virus (ToLCV) — the most devastating viral disease of tomato in the Indian subcontinent. ToLCV causes annual losses exceeding ₹3,000 crore in Indian tomato production, particularly severe in tomato belts of Karnataka, Andhra Pradesh, Telangana, Maharashtra, Odisha, West Bengal and Bihar where tomato is grown on over 800,000 hectares. The B biotype is an especially aggressive invasive strain that emerged in India in the 1990s and has displaced native biotypes — it is more polyphagous (attacks over 500 plant species), more fecund (lays more eggs), more virus-efficient (better at transmitting begomoviruses) and more insecticide-resistant than native biotypes. Once a tomato plant is infected with ToLCV, it cannot be cured — the disease causes characteristic upward leaf curling, stunting, reduced fruit set and yield loss of 50-100%. The whitefly acquires ToLCV in 15-30 minutes of feeding on an infected plant and can transmit it for life (persistent transmission, circulative). IPM with virus-free nursery stock (most critical preventive measure — most ToLCV infections originate from infected transplants), resistant varieties (carrying Ty-1, Ty-2, Ty-3 resistance genes — Arka Rakshak, Arka Samrat, Pusa Ruby), immediate roguing of infected plants (prevents secondary spread), yellow sticky trap monitoring, biological control (Encarsia parasitoid, Amblyseius predatory mite), reflective mulches (silver mulch repels whiteflies), and need-based insecticide rotation provides effective and sustainable control. The pest is most severe in continuous tomato cropping and in areas where weed hosts serve as virus reservoirs. Climate change is expanding the range of the whitefly into previously cooler tomato-growing regions, making the pest an increasing concern.